The invention herein resides generally in the art of through-flow blowers. More particularly, the present invention relates to a cooling fan that piggy backs the motor assembly included in the through-flow blower.
Through-flow blowers are generally known for drawing in air which is then re-oriented into another direction. These blowers typically draw the air through a series of interleaved motor-driven rotating fans and stationary fans to enhance the force of the air generated by the blower. This air may be used as working air such as with vacuum cleaners, furnace blowers or the like. The air, once drawn into the blower, typically swirls within the shell of a housing and is exhausted tangentially outwardly.
Currently internal turbulence within the attached motor housing, as a result of the internal features of the housing, is relied upon to dissipate the heat generated by the motor windings. Although this turbulence is effective in most instances for cooling the motor windings, in certain instances excessive heat is known to be generated. This excessive heat can lead to motor damage and related structural failures. In one application it has been found that the temperature between the windings and the ambient air can be as high as 96xc2x0 C. Therefore, there is a need to facilitate/enhance the air flow over the motor windings for motors used in through-flow blowers.
In light of the foregoing, it is a first aspect of the present invention to provide a through-flow blower with a cooling fan.
Another aspect of the present invention is to provide a through-flow blower as set forth above, which couples a fan assembly to a motor.
Still a further aspect of the present invention is to provide a through-flow blower assembly, as set forth above, in which the motor is a brushless configuration having a stator assembly and a rotor assembly and wherein the rotor assembly has at least one opening therethrough.
Yet a further aspect of the present invention is to provide a through-flow blower, as set forth above, in which a cooling fan is coupled to the rotor assembly so as to draw cooling air through the opening and over the motor windings to dissipate heat in a more efficient manner.
Yet a further aspect of the present invention is to provide a through-flow blower, as set forth above, wherein the cooling fan has an outer diameter that is no larger than the outer diameter of the rotor.
The foregoing and other objects of the present invention, which shall become apparent as the detailed description proceeds, are achieved by a through-flow blower comprising; a working air fan assembly having an axial opening; a housing coupled to the working air fan assembly, the housing having an exhaust port; a motor assembly carried in the housing and rotating the working air fan assembly, the motor having a stator and a rotor, the rotor having at least one opening therethrough; and a cooling fan connected to the rotor, such that as the rotor rotates cooling air drawn through the opening.
Other aspects of the present invention are attained by a through-flow blower assembly comprising; a housing having a tangential exhaust port; a motor assembly carried by the housing, the motor assembly having a stator and a rotor, the rotor rotating a shaft when the motor assembly is energized, the rotor having openings therethrough; a fan shell having an axial opening; at least one rotating fan carried by the shaft, the at least one rotating fan drawing working air through the axial opening and exhausting the working air through the exhaust port, the at least one rotating fan having a diameter larger than the rotor; and a cooling fan having a fan disc and a fan ring, the fan disc connected to the fan ring by a plurality of blades, the fan ring having an eye that is directly adjacent the rotor openings, the cooling fan having a diameter no larger than the rotor.
These and other objects of the present invention, as well as the advantages thereof over existing prior art forms, which will become apparent from the description to follow, are accomplished by the improvements hereinafter described and claimed.